Auto merge of #28546 - yvt:feat-cow-infra, r=jdm

Implement `Location`'s custom internal methods

This PR partly resurrects #16501 and introduces the use of principals object to associate objects and Realms with origins. Using this infrastructure, this PR implements [the custom internal methods][1] of the `Location` interface, which is "maybe-cross-origin".

Unimplemented/incomplete things:

 - Other maybe-cross-origin interfaces, namely `WindowProxy` and `DissimilarWindowLocation`, aren't implemented correctly yet (causing most test cases of `tests/wpt/web-platform-tests/html/browsers/origin/cross-origin-objects/cross-origin-objects.html` to fail).
     - `WindowProxy`: #28556
 - [The "perform a security check" operation][2] and `Location`'s non-cross-origin properties' relevant `Document` origin checks aren't implemented either (not sure if they are covered by the existing tests).
 - There are a slight deviation from the standard and inefficiency in `CrossOriginGetOwnPropertyHelper`'s current implementation.
     - #28557

[1]: https://html.spec.whatwg.org/multipage/#the-location-interface
[2]: https://html.spec.whatwg.org/multipage/browsers.html#integration-with-idl

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #16243 and make some progress in #2382

---
- [x] There are tests for these changes OR
- [ ] These changes do not require tests because ___

Cargo.lock

@@ -3814,7 +3814,7 @@ dependencies = [
 [[package]]
 name = "mozjs"
 version = "0.14.1"
-source = "git+https://github.com/servo/rust-mozjs#a8b688ad32a852172536443d77baa844f59a23fa"
+source = "git+https://github.com/servo/rust-mozjs#09edacd032fadc861b0cb3a70711a5c8a9bd7f8e"
 dependencies = [
  "cc",
  "lazy_static",